dial up working w/win98 but not winXP pro

[BullsOnParade]

I log into my work network via dial up and all it requires is
configuring some settings in the tcp/ip settings window.

I've coppied these settings exactly over to my machine
running xp and it attempts to log on but fails to connect.
I've tried running xp on the machine that's able to log on
and it still doesn't work.

Any suggestions ?

~bulls